Hobbing machine



Aug. 4, 1942.

Original Filed July 2l. 19372 F. H. ADAMS ET AL HOBBING MACHINE 5sheets-sheet l1 1N VENTOR D NS A ORNEY.

Aug. 4, 1942. F. H. ADAMS TAL 2,292,260

' `.HolsBING MACHINE original Filed July 21, 1932 5 Sheets-Sheet 2 lillAug. 4, 1942. i H. ADAMS ET AL 2,292,260

HOBING MACHINE Original Filed July 2l, 1932 5 Sheets-Sheet 5 INVENTORS/C/ PA fw( /7 A DAMS BY WML/AM /75 STA/@L55 x A ORNEYS.

Aug- 4, 1942- F. H. ADAMS ET AL 2,292,260

, HOBBING MACHINE Original Filed July 2l, 1932 5 SheGtS-Sheet 4 fi l l lWin All Wm' fw @y 4 m mw l I .BY ifa/MMM /z 554/155 --b v QWWMM Aug. 4,1942.

F. AH. ADAMS ETAI.`

HOBBING MACHINE 5 Sheets-Sheet 5 original Filed 'July 21,1932

INVENTORS. f7. ADAMS fPA/wr WML/AN H STAPLES 1 ii 'j' AMS.

Patented Aug. 4, 1942 HOBBING MACHINE Frank H. Adams and William H.Staples, Cleve- 'land Heights, Ohio, assignors to The Cleveland HobbingMachine Company,

corporation of Chio Cleveland, Ohio, a

Original application July 21, 1932, Serial No.

623,830. Divided 6 Claims.

The present invention relates to metal working machines and moreparticularly to rotary gear cutting or hobbng machines, and thisapplication is a division of our copending application, Serial Number623,830, filed July 21, 1932, entitled Hobbing machine, upon whichapplication United States Patent No. 2,048,173, issued July 21, 1936.

An object of the present invention is the provision of a novel meansfor` effecting relative movement between the tool and work of a metalworking unit comprising relatively movable tool and work supportscarried by a rotatable turret.

Another object of the invention is the provision of a novel means forcontrolling relative movement between the tool and work of a metalworking unit comprising relatively movable tool and Work supportscarried by a rotatable turret.

Another object of the invention is the provision of a novel metalworking machine comprising relatively movab-le tool and work supportscarried by a rotatable turret and means for producing relative movementbetween the tool and work supports.

Another object of the invention is the provision of a novel metalworking machine comprising relatively movable tool and work supportscarried by a rotatable turret and means for producing relative movementbetween the tool and vwork supports at different speeds controlled bythe movement of one of the supports.

Another object of the invention is the provision of a novel metalworking machine comprising relatively movable tool and work supportscarried by a rotatable turret, and a cooperating lead screw and nut orproducing relativeA movement between the tool and work supports atdifferent speeds. I Y

The invention resides in certain novel features, details ofconstruction, and combinations and arrangements of parts, and furtherobjects and advantages thereof will be apparent to those skilled in theart to which it pertains from the following description of the'preferred embodiment thereof described with reference to theaccompanying drawings, in which similar reference characters representcorresponding parts throughout the several views, and in which Fig. 1 isa perspective view of a hobbng machine embodying the present invention;

Fig. 2 is a section of the machine shown in Fig. 1 approximately on thecenter line, with portions shown in elevation;

Fig. 3 is an enlarged section appropriately on and this applicationAugust 17, 1935, Serial No. 36,708

the line 3-3 of Fig. 4 looking in the direction of the arrows, withportions shown in elevation;

Fig. 4 is a front elevation with portions broken away, of the deviceshown in Fig. 3, looking from the right as viewed in Fig. 3; Y

Fig. 5 is a View on the lines 5--5 of Figs. 3 and 4 looking in thedirection of the arrows;

Fig. 6 is a section on the line 6-6 of Fig. 4 looking in the directionof the arrows, and

Fig. 7 is a section on the line 1-1 of Fig. 4 looking in the directionof the arrows. Y A

The preferred embodiment of the invention is illustrated as embodied ina machine somewhat similar to the machines illustrated in United StatesPatent Nos. 1,732,700; 1,878,656; and 1,973,133, and only those parts ofthe machine are illustrated which are necessary to convey a completeunderstanding of the invention to those skilled in the art.

In the embodiment of the invention illustrated the turret B iscontinuously rotated 'in the drection of the arrow R, and the workvspindles loaded and unloaded as the hobbng units, of which there areeight, successively pass a definite position referred to as the loadingstation. As the hobbng units are carried in a closed path about the axisof the turret and returned to the loading station the work heads D aremoved vertically on the turret B by the feed mechanism F to feed thework past the cutter. The tool heads C are preferably adjustablysupported by the turret B for movement in a plane normal to the verticalmovement of the work heads D, but it is to be understood that a relativefeed between the tool and work spindles normal to the turret axis may beprovided in addition to the relative movement longitudinally of the workspindle axes. l f

The frame A comprises a base I6 and a central column I I about which theturret B is rotatably supported by suitable bearings I2, I3 and I4. Theturret B is rotated about the frame A by a motor I5, through the mediumof a worm I'I and worm wheel I8. The worm wheel I8 is of large diameterand is bolted on a flange member I9 secured by the bolts 20 .to thelower part of a member 2| which forms the main frame of the turret B.

Each of the tool heads C comprises a tool or hob spindle 3D rotatablysupported by a spindle member 3| which in turn is carried by a headmember 32. The spindle members 3I are adjustable about axes normal tothe naxes of the hob spindles 36, and the head members 32 are slidablysupported on horizontal ways on the turret member 2| and adjustabletherealong radially of the axis about which the turret rotates by screws33 which engage the head members and are threaded into tapped holes inthe turret member 2|. Each of the work heads D comprises a work spindle35 rotatably supported in a work head member 35 by anti-frictionbearings 31 and 38, and a tail slide 39 slidably supported on ways 40 ona Vertical projection 4| of the Work head members 36. The tail slides 39are movable on the Ways 4|) and held in any adjusted position thereon byclamp levers 42. The head members 36 are slidably supported on verticalways 43 on the turret member 2| and vertical ways 44 on a cap member 45secured to the top of the turret member by bolts 46, and movedtherealong by mechanism hereinafter referred to. A collapsible wayguard41, not shown in Figs. 2 et seq. is used to protect the ways 43 fromchips etc.

The tool and work spindles 3! and 35 respectively are rotated atpredetermined relative speeds by a motor 34 supported on an adjustableplatform 43 on the top of the column and operatively connected to ashaft 49 through a flexible drive 55. A pinion keyed to the shaft 49meshes With a bevel gear 52 bolted to the upper end of a sleeve 53rotatably supported by anti-friction bearings 54 and 55 on the centralcolumn Spacer sleeves 55 and 51 position the bearings 54 and 55 on saidcolumn. A bevel gear 58 bolted to the lower end of the sleeve mesheswith a plurality of bevel pinions 59, one for each hobbing unit, keyedto short shafts 63 rotatably supported in the turret member 2| byanti-friction bearings 5| and 62. The drives for the various hobbingunits from the gear 58 are duplicates and only one thereof Will bedescribed in detail.

The shaft 60 is operatively connected to and drives a spline shaft 63through a friction plate clutch 64 the driven member of which is splinedto said shaft 63. The shaft 63 is rotatably supported in a member 55bolted to the turret member 2|, and the head member 32 by a bevel gear66 splined thereto and an anti-friction bearing 61 and an anti-frictionbearing 68, respectively. The clutch 64 is adapted to be either manuallyor automatically operated in predetermined timed relation to the otheroperation of the machine through mechanism designated in general by thereference character 69 adapted to be automatically operated by cammechanism 13 controlled by the vertical movement of the work head D. Thehob spindle 3E! is driven from the shaft 63 through miter gears 1| and12 keyed to the shaft 53 and a short shaft 13 rotatably supported in thespindle member 3|, and change gears, not shown, one of which is keyed tothe shaft 13 and the otherto the spindle shaft 3G. The spline shaft 63permits adjustment or movement of the hob head C radially of the turretaxis without interruption of the hob spindle drive, and the miter gears1| and 12 permit angular adjustment of the spindle member 3| and the hobspindle 30 about the aXis of the shaft 63.

The work spindle 35 is driven from the shaft 63 through the followingmechanism: bevel gear |56, previously referred to; bevel gear keyed tothe upper end of a vertical shaft 15 rotatably supported by ananti-friction bearing 11 in the member 65; the shaft 15; bevel gear 85!rotatably supported in a projection 8| on the rear of the Work headmember 35 and splined to the lower end of the shaft 15; bevel gear 82,continuously in mesh with bevel gear 80, keyed to a short shaft 83 theother end of which carries a spur gear 34 also keyed thereto; the shaft83 and the spur gear 84; spur gear 85, keyed to a shaft 85 rotatablysupported on the Work head member 35, in mesh with the gear 84; changegears 81 a shaft 88 rotatably supported in the member 35 and connectedto one end of the train of change gears 81; and a W-orm 89, see Fig. 3,keyed to the shaft 88 and in mesh with a Worm Wheel 90 keyed to the workspindle 35.

Oil is supplied to the various bearings by a cascade system whichincludes a pipe 91 through which oil is pumped from a reservoir in thebase of a machine by a pump 98 of any desired construction, to a smallreservoir 93 at the top of the column Il. From the reservoir 99 the oilflows down the outer surface of the column lubricates the bearings 54,55,- I2, |3, etc., and over the bevel gear 52 onto a ledge |30 formedintegral with the cap member 45. From the ledge |50 the oil is conductedby a pipe or pipes |6J| to a trough on the top of the turret member 2|from which it passes to the bearings 6|, 52. Oil is also conducted fromthe reservoir S9 to the front bearings of the tool head by pipes |53,see Fig. 1.

The lubricating and cooling uid for the cutting tools is supplied from areservoir l0 in the base |0 of the machine, from where it is pumped by apump ||2 to a small annular reservoir ||4 at the top of the turret Bthrough pipes |5 and H6, connection ||1, and pipe H8. The pipe H5projects up through the center of the column and the connection ||1 isbent to accommodate the shaft 49. The reservoir ||4 is provided with anoverfiow pipe |23. A plurality of nozzles E22, one at each hobbing unit,are connected to the reservoir ||4 by pipes |23. The flow of fluidthrough the nozzles |22 is controlled by valves |24 either manually orautomatically operated. The valves |24 preferably operatively connectedby a rod |25 to the clutch operating mechanism 69 and operated therebyin such a manner that the flow of fluid is interrupted when the spindles30 and 35 are stationary in the loading station, and uninterruptedduring the rotation of said spindles.

As previously stated the hobbing units are carried in a closed circularpath about the axis of the turret B as the same rotates, and the workloaded and unloaded at one or more positions referred to as loadingstations. In the embodiment of the invention illustrated, only oneloading station is employed at which position the nished Work is removedand a new work piece inserted without interrupting the rotation of theturret, and as the units are moved in a closed path back to the loadingstation the work heads D are moved along the vertical ways 43 and 44 tofeed the work supported thereby past the cutters or hobs carried on thespindles 3D. As the hobbing units successively pass the loading station,the finished work pieces are removed, a rapid traverse movement impartedto the work heads D to lower the same to the starting position, new Workpieces inserted and the work heads given a rapid traverse movement inthe reverse direction to bring the work up to the tool, after which thefeed movement is imparted to the Work heads. 'Ihe mechanism forperforming these operations is the same foreach work head D and only onethereof will be described in detail.

A bracket secured to the lower ends of the ways 43 by the bolts |3| and|32 rotatably supports a nut N continuously in engagement with a leadscrew |33 rotatably secured in a suitable aperture |34 in the work headmember 36. An anti-friction thrust bearing |35 positioned between aflange on the upper end of the nut and the bracket |36 takes thedownward thrust of the nut N. The lead screw |33 is rotated inpredetermined timed relation to the other operations of the machine,from the work spindle 35 through change gears indicated in general bythe reference character |36. An anti-friction thrust bearing |31 ispositioned between the lead screw |33 and the work head member 36 totake the weight of the work head.

VAs illustrated, the feed movement is imparted to the work head D by therelatively slow rotation of the lead screw |33, and the nut N is adaptedto be rapidly rotated in either direction to impart the rapid traversemovement to the head by the following mechanism: A bevel gear |46 keyedto the nut N is continuously in mesh with a bevel gear |4| fixed on oneend of a shaft |42 rotatably supported in the bracket |30. The shaft |42is adapted to be driven at a comparatively high speed by a shaft |43coupled to the lower end of the shaft 16, through a bevel gear |44 keyedto the lower end of shaft |43 and continuously in mesh with bevel gears|45 and |46 rotatably supported on shaft |42. The bevel gears |45 and|46 are adapted to be selectively connected to the shaft |42 by aclutch, the movable element |41 of which is keyed to the shaft |42 in amanner Well known in the art.

The movable clutch element |41 is shifted to connect and disconnecteither of the gears |45 and |46 with the shaft |42 through the medium ofa yoke member |50 carried by a rod |5| slidably supported in a suitableaperture in Athe bracket |30. A spring pressed plunger |52 engagesnotches |53 in the rod |5| and retains the clutch element |41 in itsneutral or either of its engaged positions. A vertical shaft |54rotatably supported by the bracket |30 and a bracket |55 secured to theturret member 2|, carries an arm |56 on the lower end thereof providedwith a sl-otted end which engages a pin |51 xed in a member |53 formedintegral with the yoke member 66. A hand lever |59 secured to the upperend of the vertical shaft |54 provides for manual operation thereof andthe same is adapted to be actuated automatically to shift the movableclutch element |41 through the medium of a collar 566 xed to the shaft|54 which carries a projection |6| formed integral therewith adapted toengage in a cam slot |62 formed in a member |63 secured to the work headmember 36. In the present instance the cam slot |63 is so formed thatthe clutch element |41 is automatically shifted to neutral position asthe work head D reaches its lower position and again as the work isbrought up to the tool by the inclined surfaces |64 and |65, but may beformed to connect either of the gears |45 and |46 with the shaft |42 atpredetermined intervals etc., controlled by the vertical movement of thework head D.

In operation it is desirable to prevent rotation of the nut N during therotation of the lead screw |33 and topermit free rotation thereof duringthe rapid traverse movement of the work heads D. To effect this result aplurality of spring pressed plungers |66 and |61 slidably supported insuitable apertures in the bracket |30 are adapted to engage the outsidesurface of said nut. The plungers |66 and |61 are held from engagementwith the nut N when the same is being rotated by a wedge-shaped member|68, the upper end of which engages between the plungers |66 and |61.The lower end of the member |68 engages in a slot |10 in the rod |5|when the clutch element |41 is in its neutral position and rides up onsaid rod when the same 'is shifted to connect either of the gears |45and |46 with the shaft |42.

It is believed that the operation of the machine will be apparent fromthe foregoing description, suffice it to say that the turret B iscontinuously rotated about the frame A, and the tool and work spindlesof each unit rotated in predetermined timed relation to each other bythe motor 34. As the bobbing units are carried in a closed path by therotation of the turret B the work pieces supported by the work heads Dare fed vertically past the cutters by the lead screws |33, which aspreviously described are driven at a comparatively slow speed from thedrive for the work spindle. As the hobbing units are successivelybrought to the loading station by the rotation of the turret B, therotation of the tool and work spindles and the lead screw of thatparticular unit is stopped by clutch 68 which interrupts the drivethereto without disturbing the continued operation of the other units.As soon as the finished work is removed from the unit in the loadingstation, the hand lever |59 is moved to connect the shaft |42 to thesplined shaft 16 and rotate the nut N in a direction to lower the workhead D. As the work head D reaches its lower position the clutch element|41 is returned to neutral position by the inclined surface |64 of thecam slot |63. After a new work piece has been inserted in the workholder, the clutch |41 is manually engaged and the lever |59 moved in areverse direction to rotate the nut N in a direction to bring the workup to the cutting position, whereupon the shaft is automatically movedto the neutral position by the engagement of the projection |`6| withthe inclined surface |65 of the cam slot |62 the tool, work spindle, andlead screw |33.`

From the foregoing description it will be apparent that a new andimproved machine and feed mechanism therefor has been provided. As onealternative construction it is suggested that the feed screw might bedriven from the motor 34 independent of the spindle drive and a clutchinterposed in the drive whereby the feed could be interrupted withoutstopping the work spindle. If desired the work and tools may beinterchanged, or the lead screws positioned above the tool spindlesinstead of below, as illustrated. Each unit may also be driven by anindividual motor. The machine may be set up to machine various pieces ofwork other than splined shafts, spur gears, spiral gears, bevel gears,spiral bevel gears, etc., and the cutter employed may be either acylindrical, conical or face hob, or any mill cutter etc. A constantfriction brake may be substituted for the mechanism shown for holdingthe nut N against rotation during rotation of said screw, etc. Theadjustments of the spindles permit the cutting of such articles asspiral bevel gears with face hobs.

The preferred embodiment of the invention shown and described is merelyillustrative of the invention and we do not wish to be limited theautomatic release of the l without interrupting the drive to thereby. Weparticularly point out and claim as our invention the following:

l. In a machine of the character described, the combination of a frame,a tool spindle rotatably supported by said frame, a work head slidablysupported by said frame for vertical movements, a work spindle rotatablysupported in said work hea'd, means for rotating said spindles in timedrelation to each other, means comprising a lead screw and a cooperatingnut for `moving said work head, means operatively connected to thefirst-named means adapted for producing relative rotation between saidlead screw and its cooperating nut at a relatively slow speed, meansoperatively connected to the rst named means adapted for producingrelative rotation between said lead screw and its cooperating nut at arelatively fast speed, said last-named means comprising a movable clutchmember, and means automatically actuated in timed relation to themovement of said work head for moving said movable clutch member.

2. In a machine of the character described, the combination of a frame,a tool spindle rotatably supported by said frame, a work head slidablysupported by said frame for vertical movement, a work spindle rotatablysupported in said work head, a, cam carried by said work head, means forrotating said spindles in timed relation to each other, means comprisinga lead screw and a cooperating nut for moving said Work head, meansoperatively connected to the first-named means for producing relativerotation between said lead screw and its cooperating nut at a relativelyslow speed, means for producing relative rotation between said leadscrew and its cooperating nut at a relatively fast speed, saidlast-named means comprising a movable element adapted to control theactuation thereof, and means controlled by said cam for moving saidmovable member.

3. In a machine of the character described, the combination of a frame,a tool spindle rotatably supported by said frame, a work head slidablysupported by said frame for vertical movement, a work spindle rotatablysupported in said work head, means for rotating said spindles in timedrelation to each other, means comprising a lead screw and a cooperatingnut for moving said work head, means operatively connected to thefirst-named means for producing relative rotation between said leadscrew and its cooperating nut at a relatively slow speed, meansoperatively connected to the first-named means for producing relativerotation between said lead screw and its cooperating nut at a relativelyfast speed, said last-named means comprising a movable clutch member,and cam means automatically actuated in timed relation to the movementof said work head for moving said movable clutch member.

4. In a machine of the character described, the combination of a frame,a tool spindle rotatably supported by said frame, a work head slidablysupported by said frame for vertical movement, a work spindle rotatablysupported in said Work head, a cam on said work head, means for rotatingsaid spindles in timed relation to each other, means comprising a leadscrew and a cooperating nut for moving said work head, means operativelyconnected to the rst-named means for producing relative rotation betweensaid lead screw and its cooperating nut at a relatively slow speed,means operatively connected to the rst-named means for producingrelative rotation between said lead screw and its cooperating nut at arelatively fast speed, said last-named means` comprising a movableclutch member, and means operatively engaging said cam for moving saidmovable clutch member.

5. In a machine of the character described, the combination of a base, aturret rotatably supported by said base, cooperating tool and Workspindles rotatably carried, by said turret, means for rotating saidspindles in timed relation to each other, means for rotating said turretwhereby said spindles periodically travel through a loading station,means comprising a lead screw and a cooperating nut for producingrelative movement between said spindles in a vertical direction, meansoperatively connected to the first-named means adapted for producingrelative rotation between said lead screw and its cooperating nut at arelatively slow speed, means operatively connected to the rst-namedmeans adapted for producing relative rotation between said lead screwand its cooperating nut in different directions and at relatively fastspeeds, said last-mentioned means comprising a movable clutch elementand means automatically actuated in timed relation to the movement ofone of said spindles for moving said movable clutch element.

6. In a machine of the character described, the combination of a base, aturret rotatably supported by said base, a tool spindle rotatablysupported by said turret, a work head slidably supported by said turret,a work spindle rotatably supported in said work head for verticalmovement, a cam carried by said work head, means for rotating saidspindles in timed relation to each other, means comprising a lead screwand a cooperating nut for moving said work head, means operativelyconnected to the first-named means adapted for producing relativerotation between said lead screw and its cooperating nut at a relativelyslow speed, means operatively connected to the first-named means adaptedfor producing relative rotation between said lead screw and itscooperating nut at a relatively fast speed, said last-named meanscomprising a movable clutch element, and means controlled by said camfor moving said movable clutch element.

FRANK H. ADAMS. WILLIAM H. STAPLES.

